Traditional tape libraries use a robot to move tape cartridges from shelves within a library to one or more tape drives when requested. At that point, the data stored on the tape cartridges can be linearly read since tape is a linear medium.
Unfortunately, tape cartridges have latency and wear limitations and thus are not ideal for the quick and efficient retrieval of data as this reduces the value for long term storage use. Additionally, these traditional tape libraries with robots can be expensive to set up and operate. In particular, they often require precise mechanical engineering to setup and maintain.